Signal turn arrows not a simple solution for traffic problems

We get lots of letters each year from readers suggesting that protected turn arrows be added to the traffic signals in certain intersections around town. Most of the intersections mentioned as prime candidates make sense, and making it safer to execute turns is always ideal. But the process of adding turn arrows to traffic signal cycles is one that involves careful consideration and study, because even though it often seems the best thing to do, certain issues have to be weighed such as traffic volume in the area and the effect the added turn arrow will have on traffic flow. The intersection we've heard about a lot over the years is southbound Pasadena Avenue at Central Avenue. Motorists wanting to turn left from Pasadena onto eastbound Central find the going to be pretty rough. One reader wrote:

I've lived in St. Petersburg for 25 years, and continue to wonder why a busy intersection still does not have an arrow for safety. Pasadena Avenue and Central Avenue is the hardest turn to accomplish with cars flying over the hump, (former railroad tracks). There have been many accidents there. Most of the time you have to continue past Central over the hump and make a U-turn to come back and head east down Central. Will there ever be a turn signal?"

Keith Crawford, a signals/systems engineer with DOT, said the intersection was last studied in 2005 and there were low left turn volumes and "little in the way of left turn crashes."

Crawford said that adding a protected turn arrow at the time would be too great a toll on through- and east-west traffic than the convenience it might afford left-turning traffic.

"The irony is that the east-west directions, which have left-turn arrows, had 14 left turn crashes recorded in 2004 through 2007 while north-south recorded none," Crawford said. The good news is that the DOT will conduct a new study of left-turn delay at Pasadena and Central.

Dueling condo access

Here's another Pasadena Avenue question we passed along to the DOT from reader Jim Heady:

"Dear Doc,

I am writing with concerns about the entrances to two different condominiums along the Corey Causeway. DOT installed a stop light at the entrance to Harbourside condominiums at Sailboat Key some time ago. There is a caution light at the entrance to Bay Island Condos. While I understand there is not enough distance between the two to allow for a traffic light at each, the volume of traffic exiting Bay Island seems to be far greater than Harbourside ... even taking into account the small amount of traffic from the commercial boats across from Harbourside that also use the light. Do you think DOT would consider doing a study and actually count the amount of traffic at each intersection, then make a decision on which area truly needs a stop light?"

We checked with DOT's Kris Carson who told us that a study of the intersection of Pasadena Avenue and Sun Island Drive was conducted in April based on requests from residents of the Bay Island community. This was a bit of an unusual situation because the condominium has an exit signal at Matthews Road and Huffman Way, which allows residents to enter and exit through an area behind Palms of Pasadena Hospital. However, the Huffman Bridge, connecting residents to that road, was damaged and closed at the time. Carson said the caution signal appeared to be an alternative to repairing the bridge, which is owned by the Sun Island Association.

The traffic study, which was conducted after the Huffman Bridge was closed, found traffic volume to be insufficient to justify the signal and Carson said that once the bridge is repaired the need for this signal will go away. But there's no telling when that will be. The DOT recommends that the association repair and reopen the Huffman Bridge to traffic. The cost for the repairs has been estimated to be about $459,000, which includes design and inspection services.